This black alloy picatinny sling stud rail adapter fits to the sling/bipod stud on the stock forend, making it perfect for both your gun sling and a picatinny rail mounted accessory at the same time eg; bipod, laser, torch, sling. By adjusting the tension on the front and rear screws you can change the vertical angle of the picatinny rail to align with the barrel instead of the stock. 4 slot picatinny rail alloy adapter 68mm long rubber base pad 75mm long rubber pad protects damage to the foreend rear facing 45* swiveled sling stud for sling or bipod simultaneously use sling/bipod and a picatinny rail mounted accessory Fitting instructions included NOTE: this is not a Caldwell brand as in the video.